package archetype

import (
	"errors"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"strconv"
	"strings"
)

type EurekaAdapter struct {
	Root   string
	Config map[ConfigOption]string
}

func (self *EurekaAdapter) Init(cfg *Config) {
	fileInfo, err := os.Stat(cfg.Root)
	if os.IsNotExist(err) {
		panic("SSG content root does not exist! Ensure your configs are correct or create it!")
	} else if !fileInfo.IsDir() {
		panic("SSG content root is not a directory!")
	}

	self.Root = cfg.Root
	self.Config = make(map[ConfigOption]string)
	// TODO: read config.h and build self.Config
	err = self.readCfg()
	if err != nil {
		panic("config.h is malformed!")
	}
}

func (self *EurekaAdapter) Name() string {
	return "eureka"
}

func (self *EurekaAdapter) EditableSlugs() bool {
	return false
}

func (self *EurekaAdapter) BuildOptions() []string {
	return []string{"twtxt"}
}

func (self *EurekaAdapter) GetConfig() map[ConfigOption]string {
	return self.Config
}

func (self *EurekaAdapter) SetConfig(cfg map[ConfigOption]string) error {
	self.Config = cfg
	return self.writeCfg()
}

func (self *EurekaAdapter) ListPages() map[string]string {
	files, err := ioutil.ReadDir(
		filepath.Join(self.Root, "inc"))

	if err != nil {
		panic(err.Error())
	}

	pages := map[string]string{}
	for _, file := range files {
		filename := file.Name()
		if strings.HasSuffix(filename, ".htm") {
			pages[filename] = strings.Replace(
				strings.TrimSuffix(filename, ".htm"), "_", " ", -1)
		}
	}
	return pages
}

func (self *EurekaAdapter) GetPage(filename string) Page {
	if strings.Contains(filename, "../") || strings.Contains(filename, "..\\") {
		return Page{
			Error: "You cannot escape!",
		}
	}
	fullPath := filepath.Join(self.Root, "inc", filename)
	f, err := os.ReadFile(fullPath)

	if err != nil {
		return Page{
			Error: err.Error(),
		}
	}

	if !strings.HasSuffix(filename, ".htm") {
		return Page{
			Error: "Page file extension is not '.htm'",
		}
	}

	title := strings.Replace(
		strings.TrimSuffix(filename, ".htm"), "_", " ", -1)
	fileInfo, _ := os.Stat(fullPath)
	content := string(f[:])

	return Page{
		Title:   title,
		Content: content,
		Edited:  fileInfo.ModTime(),
	}
}

func (self *EurekaAdapter) FormatPage(raw string) string {
	// TODO: implement Eureka formatter to show preview
	return raw
}

func (self *EurekaAdapter) FormattingHelp() string {
	// TODO: show Eureka formatting guide
	return "help!"
}

func (self *EurekaAdapter) CreatePage(slug, title, content string) error {
	// eureka creates titles from slugs, so we transform the title into the slug
	slug = strings.ReplaceAll(title, " ", "_") + ".htm"
	path := filepath.Join(self.Root, "inc", slug)

	if strings.Contains(slug, "../") || strings.Contains(slug, "..\\") {
		return errors.New("You cannot escape!")
	}

	_, err := os.Stat(path)
	if err == nil || !os.IsNotExist(err) {
		return errors.New("File already exists")
	}
	f, err := os.Create(path)
	if err != nil {
		return err
	}
	defer f.Close()
	f.WriteString(content)
	return nil
}

func (self *EurekaAdapter) SavePage(oldSlug, newSlug, title, content string) error {
	// eureka creates titles from slugs, so we transform the title into the slug
	newSlug = strings.ReplaceAll(title, " ", "_") + ".htm"

	if strings.Contains(newSlug, "../") || strings.Contains(newSlug, "..\\") ||
		strings.Contains(oldSlug, "../") || strings.Contains(oldSlug, "..\\") {
		return errors.New("You cannot escape!")
	}

	f, err := os.Create(filepath.Join(self.Root, "inc", newSlug))
	if err != nil {
		return err
	}
	defer f.Close()

	if oldSlug != newSlug {
		siteRoot := self.Config[ConfigOption{
			Name: "SITEROOT",
			Type: "string",
		}]
		htmlFile := filepath.Join(self.Root, siteRoot, oldSlug+"l")
		_, err := os.Stat(htmlFile)
		if !os.IsNotExist(err) {
			os.Remove(htmlFile)
		}
		os.Remove(filepath.Join(self.Root, "inc", oldSlug))
	}

	f.WriteString(content)
	return nil
}

func (self *EurekaAdapter) DeletePage(slug string) error {
	if strings.Contains(slug, "../") || strings.Contains(slug, "..\\") {
		return errors.New("You cannot escape!")
	}

	siteRoot := self.Config[ConfigOption{
		Name: "SITEROOT",
		Type: "string",
	}]
	htmlFile := filepath.Join(self.Root, siteRoot, slug+"l")
	_, err := os.Stat(htmlFile)
	if !os.IsNotExist(err) {
		os.Remove(htmlFile)
	}
	return os.Remove(filepath.Join(self.Root, "inc", slug))
}

func (self *EurekaAdapter) Build(buildOptions map[string][]string) BuildStatus {
	twtxt := strings.Join(buildOptions["twtxt"], " ")
	cmdArgs := []string{}
	if twtxt != "" {
		cmdArgs = append(cmdArgs, "-t")
		cmdArgs = append(cmdArgs, twtxt)
	}

	cmd := exec.Command("./build.sh", cmdArgs...)
	cmd.Dir = self.Root
	out, err := cmd.CombinedOutput()

	return BuildStatus{
		Success: err == nil,
		Message: string(out),
	}
}

func (self *EurekaAdapter) readCfg() error {
	configPath := filepath.Join(self.Root, "config.h")
	_, err := os.Stat(filepath.Join(self.Root, "config.h"))
	if os.IsNotExist(err) {
		configPath = filepath.Join(self.Root, "config.def.h")
	}
	f, err := os.ReadFile(configPath)

	if err != nil {
		return err
	}

	fileData := string(f[:])

	macros := strings.Split(fileData, "#define ")[1:]
	for _, macro := range macros {
		tokens := strings.Split(strings.TrimSpace(macro), " ")
		k := tokens[0]
		v := strings.TrimSpace(strings.Join(tokens[1:], " "))

		if strings.Contains(v, "\"") {
			if strings.Contains(v, "\\\r\n") || strings.Contains(v, "\\\n") {
				// process multiline string
				lines := strings.Split(v, "\n")
				cleanedString := ""
				for _, l := range lines {
					l = strings.TrimSuffix(l, "\r")
					l = strings.TrimSuffix(l, "\\")
					l = strings.TrimSpace(l)
					l = strings.TrimPrefix(l, "\"")
					l = strings.TrimSuffix(l, "\"")
					l = strings.ReplaceAll(l, "\\\"", "\"")
					l = strings.ReplaceAll(l, "\\n", "\n")
					cleanedString += l
				}
				self.Config[ConfigOption{
					Name: k,
					Type: "multilinestring",
				}] = cleanedString
			} else {
				cleanedString := strings.TrimSuffix(strings.TrimPrefix(v, "\""), "\"")
				cleanedString = strings.ReplaceAll(cleanedString, "\\n", "\n")
				cleanedString = strings.ReplaceAll(cleanedString, "\r", "")
				cleanedString = strings.ReplaceAll(cleanedString, "\\\"", "\"")
				self.Config[ConfigOption{
					Name: k,
					Type: "string",
				}] = cleanedString
			}
		} else if strings.Contains(v, ".") {
			_, err := strconv.ParseFloat(v, 64)
			if err != nil {
				return err
			}
			self.Config[ConfigOption{
				Name: k,
				Type: "float",
			}] = v
		} else {
			_, err := strconv.ParseInt(v, 10, 64)
			if err != nil {
				return err
			}
			self.Config[ConfigOption{
				Name: k,
				Type: "int",
			}] = v
		}
	}
	return nil
}

func (self *EurekaAdapter) writeCfg() error {
	f, err := os.Create(filepath.Join(self.Root, "config.h"))
	if err != nil {
		return err
	}

	defer f.Close()

	for k, v := range self.Config {
		switch k.Type {
		case "int":
			_, err := strconv.ParseInt(v, 10, 64)
			if err != nil {
				return err
			}
			f.WriteString("#define " + k.Name + " " + v + "\n")
		case "float":
			_, err := strconv.ParseFloat(v, 64)
			if err != nil {
				return err
			}
			f.WriteString("#define " + k.Name + " " + v + "\n")
		case "string":
			fallthrough
		case "multilinestring":
			v = strings.ReplaceAll(v, "\"", "\\\"")
			v = strings.ReplaceAll(v, "\n", "\\n\" \\\n\"")
			v = strings.ReplaceAll(v, "\r", "")
			f.WriteString("#define " + k.Name + " \"" + v + "\"\n")
		default:
			return errors.New("Unsupported config value type: " + k.Type)
		}
	}
	return nil
}